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151.
Daniela C. Granato Mariana R. Zanetti Rebeca Kawahara Sami Yokoo Romênia R. Domingues Annelize Z. Arag?o Michelle Agostini Marcelo F. Carazzolle Ramon O. Vidal Isadora L. Flores Johanna Korvala Nilva K. Cervigne Alan R. S. Silva Ricardo D. Coletta Edgard Graner Nicholas E. Sherman Adriana F. Paes Leme 《PloS one》2014,9(5)
Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules. 相似文献
152.
Silu Bhochhibhoya Massimo Pizzol Wouter M. J. Achten Ramesh Kumar Maskey Michela Zanetti Raffaele Cavalli 《The International Journal of Life Cycle Assessment》2017,22(11):1851-1863
Purpose
The main aim of the study is to assess the environmental and economic impacts of the lodging sector located in the Himalayan region of Nepal, from a life cycle perspective. The assessment should support decision making in technology and material selection for minimal environmental and economic burden in future construction projects.Methods
The study consists of the life cycle assessment and life cycle costing of lodging in three building types: traditional, semi-modern and modern. The life cycle stages under analysis include raw material acquisition, manufacturing, construction, use, maintenance and material replacement. The study includes a sensitivity analysis focusing on the lifespan of buildings, occupancy rate and discount and inflation rates. The functional unit was formulated as the ‘Lodging of one additional guest per night’, and the time horizon is 50 years of building lifespan. Both primary and secondary data were used in the life cycle inventory.Results and discussion
The modern building has the highest global warming potential (kg CO2-eq) as well as higher costs over 50 years of building lifespan. The results show that the use stage is responsible for the largest share of environmental impacts and costs, which are related to energy use for different household activities. The use of commercial materials in the modern building, which have to be transported mostly from the capital in the buildings, makes the higher GWP in the construction and replacement stages. Furthermore, a breakdown of the building components shows that the roof and wall of the building are the largest contributors to the production-related environmental impact.Conclusions
The findings suggest that the main improvement opportunities in the lodging sector lie in the reduction of impacts on the use stage and in the choice of materials for wall and roof.153.
Alessandra Mallano Silvia Zamboni Giulia Carpinelli Filippo Santoro Michela Flego Alessandro Ascione Mara Gellini Marina Tombesi Franca Podo Maurizio Cianfriglia 《BMC biotechnology》2008,8(1):68
Background
The ability of cytosine deaminase (CD) to convert the antifungal agent 5-fluorocytosine (5-FC) into one of the most potent and largely used anticancer compound such as 5-fluorouracil (5-FU) raised considerable interest in this enzyme to model gene or antibody – directed enzyme-prodrug therapy (GDEPT/ADEPT) aiming to improve the therapeutic ratio (benefit versus toxic side-effects) of cancer chemotherapy. The selection and characterization of a human monoclonal antibody in single chain fragment (scFv) format represents a powerful reagent to allow in in vitro and in vivo detection of CD expression in GDEPT/ADEPT studies. 相似文献154.
The biological function of chaperone complexes is to assist the folding of non-native proteins. The widely studied GroEL chaperonin is a double-barreled complex that can trap non-native proteins in one of its two barrels. The ATP-driven binding of a GroES cap then results in a major structural change of the chamber where the substrate is trapped and initiates a refolding attempt. The two barrels operate anti-synchronously. The central region between the two barrels contains a high concentration of disordered protein chains, the role of which was thus far unclear. In this work we report a combination of atomistic and coarse-grained simulations that probe the structure and dynamics of the equatorial region of the GroEL/GroES chaperonin complex. Surprisingly, our simulations show that the equatorial region provides a translocation channel that will block the passage of folded proteins but allows the passage of secondary units with the diameter of an alpha-helix. We compute the free-energy barrier that has to be overcome during translocation and find that it can easily be crossed under the influence of thermal fluctuations. Hence, strongly non-native proteins can be squeezed like toothpaste from one barrel to the next where they will refold. Proteins that are already fairly close to the native state will not translocate but can refold in the chamber where they were trapped. Several experimental results are compatible with this scenario, and in the case of the experiments of Martin and Hartl, intra chaperonin translocation could explain why under physiological crowding conditions the chaperonin does not release the substrate protein. 相似文献
155.
Mrcia Saladini Vieira Salles Marcus Antonio Zanetti Fernando Andr Salles 《Animal Feed Science and Technology》2008,141(3-4):233-245
To test the effect of monensin on the mineral balance of growing cattle under different environmental temperatures, 24 male steers were assigned in a 2 × 2 factorial arrangement, contrasting 0 and 85 mg monensin/animal per day at 24.3 and 33.2 °C (environmental temperatures). Monensin effect was directly modulated by the environmental temperature: it increased apparent retentions of P (P=0.066), Na (P=0.005) and K (P=0.003), at the higher temperature and decreased these apparent retentions at the lower temperature, as compared with non-supplemented animals. Monensin increased fecal Ca (P=0.037), and urinary P (P=0.002), Na (P=0.003), K (P=0.014), Mg (P=0.051) and Zn (P=0.091), with higher concentrations of these minerals in animals held at 24.3 °C and lower concentrations in those at 33.2 °C, as compared with non-supplemented animals. Monensin decreased serum Mg (P=0.001) and increased serum Zn (P=0.071) in animals at 33.2 °C and increased serum Mg and decreased serum Zn at 24.3 °C. Irrespective of temperature, monensin increased both apparent absorption (P=0.058) and apparent retention (P=0.093) of P, and also urine Cu (P=0.085). Environmental temperature modulated monensin effects on mineral balance. Monensin increased apparent retention of several minerals in animals under heat stress. 相似文献
156.
Gianni Balliano Henrietta Dehmlow Simonetta Oliaro-Bosso Matilde Scaldaferri Silvia Taramino Franca Viola Giulia Caron Johannes Aebi Jean Ackermann 《Bioorganic & medicinal chemistry letters》2009,19(3):718-723
A series of 25 compounds, some of which previously were described as inhibitors of human liver microsomal oxidosqualene cyclase (OSC), were tested as inhibitors of Saccharomyces cerevisiae, Trypanosoma cruzi, Pneumocystis carinii and Arabidopsis thaliana OSCs expressed in an OSC-defective strain of S. cerevisiae. The screening identified three derivatives particularly promising for the development of novel anti-Trypanosoma agents and eight derivatives for the development of novel anti-Pneumocystis agents. 相似文献
157.
M. Snoussi E. Noumi H. Hajlaoui D. Usai L.A. Sechi S. Zanetti A. Bakhrouf 《Journal of applied microbiology》2009,106(5):1591-1599
Aims: The ability of Vibrio alginolyticus strains isolated from Sparus aurata and Dicentrarchus labrax nursery to adhere to epithelial cell lines (Hep-2 and Caco-2), fish mucus and their ability to form a biofilm on different surfaces (glass, polystyrene, polyethylene and polyvinyl-chloride) was investigated in this study.
Methods and Results: The extracellular products were rich in enzymes and the strains were haemolytic on Wagatsuma agar and possessed several hydrolytic exoenzymes such as proteases, DNase and lipases. Most strains tested were multiresistant to the 17 antibiotics tested including those used in the farm to treat vibriosis.
Conclusions: These bacteria were able to form a biofilm on all the surfaces tested and the cell density was the highest on the PVC surface followed by that on the glass slides, polystyrene and the polyethylene surface. More than 50% of the tested strains were adhesive to the epithelial cell lines (Hep-2 and Caco-2).
Significance and Impact of the Study: These properties allow these bacteria to survive, proliferate and persist in all stages of fish rearing nursery even after seawater treatment with UV light. 相似文献
Methods and Results: The extracellular products were rich in enzymes and the strains were haemolytic on Wagatsuma agar and possessed several hydrolytic exoenzymes such as proteases, DNase and lipases. Most strains tested were multiresistant to the 17 antibiotics tested including those used in the farm to treat vibriosis.
Conclusions: These bacteria were able to form a biofilm on all the surfaces tested and the cell density was the highest on the PVC surface followed by that on the glass slides, polystyrene and the polyethylene surface. More than 50% of the tested strains were adhesive to the epithelial cell lines (Hep-2 and Caco-2).
Significance and Impact of the Study: These properties allow these bacteria to survive, proliferate and persist in all stages of fish rearing nursery even after seawater treatment with UV light. 相似文献
158.
159.
Giorgio Mancinelli Fabio Vignes Franca Sangiorgio Annunziata Mastrolia Alberto Basset 《International Review of Hydrobiology》2009,94(4):419-435
The potential contribution of microfungi to reed decomposition in a coastal habitat (Le Cesine Lagoon, Italy) was investigated under laboratory and field conditions. Leaf pack mass and surface loss, ergosterol content and O2 uptake were used to construct carbon budgets and an empirical ergosterol‐to‐O2 uptake relationship based on literature data was used to estimate the contribution of microfungi. Under laboratory conditions, reed carbon loss was entirely due to leaching and microbial respiration. In contrast, C losses observed in the field were accounted for by microbial respiration and macroinvertebrate shredding almost equally. Microfungi were estimated to account for 98% and 69% of microbially‐respired carbon under laboratory and field conditions, respectively. Our results provide a preliminary, quantitative assessment of microfungal contribution to reed decomposition in brackish habitats. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
160.
Molecular dynamics simulations have been carried out to characterize the structure and solubility of chitosan nanoparticle‐like structures as a function of the deacetylation level (0, 40, 60, and 100%) and the spatial distribution of the N‐acetyl groups in the particles. The polysaccharide chains of highly N‐deacetylated particles where the N‐acetyl groups are uniformly distributed present a high flexibility and preference for the relaxed two‐fold helix and five‐fold helix motifs. When these groups are confined to a given region of the particle, the chains adopt preferentially a two‐fold helix with ? and ψ values close to crystalline chitin. Nanoparticles with up to 40% acetylation are moderately soluble, forming stable aggregates when the N‐acetyl groups are unevenly distributed. Systems with 60% or higher N‐acetylation levels are insoluble and present similar degrees of swelling regardless the distribution of their N‐acetyl groups. Overall particle solvation is highly affected by electrostatic forces resulting from the degree of acetylation. The water mobility and orientation around the polysaccharide chains affects the stability of the intramolecular O3‐HO3(n)···O5(n +1) hydrogen bond, which in turn controls particle aggregation. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 448–460, 2011. 相似文献